Thomas Allnutt Brassey, 2nd Earl Brassey, styled Viscount Hythe between 1911 and 1918, was born on March 7, 1863, in Battle, Sussex, England, the only son of Thomas Brassey, 1st Earl Brassey (1836-1918), by his first wife Anna Allnutt Brassey (1839-1887). 
 
He was a British peer, who was for many years editor or joint editor of Brassey's Naval Annual. Brassey was educated at Eton and Balliol College, Oxford. He was an honorary Lieutenant in the London Brigade of Royal Naval Artillery Volunteers from 1888 to 1892. He acted as Assistant Private Secretary to Earl Spencer during the time the latter was First Lord of the Admiralty (1892–95), and in 1894 was Assistant Secretary of the Royal Commission on Opium that his father chaired. Brassey was appointed a captain in the Queen's Own West Kent Yeomanry in 1898. After the outbreak of the Second Boer War in late 1899, Brassey volunteered for active service and was commissioned Captain of 69 (Sussex) Company of the Imperial Yeomanry in 1900. While in South Africa, he served as acting Civil Commissioner for the British government at Pretoria in 1901, following its surrender by the Boers the previous year. He later became Lieutenant-Colonel in command of the West Kent Yeomanry in 1910, retiring in 1914. He was awarded the Territorial Decoration in 1909. After the outbreak of the First World War, he raised a second battalion to this regiment for home service, which he commanded until 1916, remaining in the Territorial Force Reserve. Brassey was editor of The Naval Annual (1892-1899, 1902-1914, 1919). He stood unsuccessfully for election to Parliament as Liberal candidate for Epsom in 1892, for Christchurch in 1895 and 1900 and Devonport in 1902. He was Mayor of Bexhill-on-Sea in 1909 and served as a Deputy Lieutenant and Justice of the Peace for Sussex. He was managing director of lead mining and smelting companies in Italy and Sardinia. He was Knight of Grace of the Order of St. John of Jerusalem and Commander of the Order of the Crown of Italy.
 
In 1889, he married Idina Mary Nevill (1865–1951). He died on November 12, 1919, in London, England.